The invention relates to a system for downloading micro code to a memory device, particularly FLASH memory.
In high speed magnetic tape reading and writing units ("tape streamers"), code has previously been stored in memory, typically an EPROM, PROM or ROM. Each of these memory devices are well known in the art. New devices, however, are changing from these conventional memory devices to devices using FLASH memory. The primary advantage of using FLASH memory is the easy upgrade necessary to change the prior micro code to the new code. The new code can be loaded into the FLASH memory through several different paths. A natural path would be to read a file into the FLASH memory. This, however, requires the use of a read command from a host system.
A problem occurs when a customer first believes data is to be read onto a standard data cartridge and tape drive, and then believes this same data is code data for its FLASH memory. The data is then incorrectly transferred from the tape to the FLASH memory. To enable upgrade of large inventories of streamers with new codes, it would be desirable if it would be sufficient to apply power only to the drive and insert the cartridge containing the upgrade code. This would mean, however, that the drive would have to undertake a check read of each inserted cartridge to check for the possibility of that cartridge containing an upgrade code. This process is time-consuming, as well as repetitive, when data is being read when it is not required.
It is a further problem in this technology that tapes begin their code with some special data pattern indicating to the tape drive that this code is to be read into its memory. The problem arises on a data cartridge in which the initial code contains the same pattern for transferring the code to the memory. The tape drive will automatically begin the transfer of data once the pattern is detected.